Walsh began by revealing that her character (Dr. Addison Montgomery) was originally only meant to be a temporary recurring character on “Grey’s,” so imagine her surprise when executive producers Shonda Rhimes and Betsy Beers called her into their office.

“I didn’t expect this,” said Walsh. “Whenever I got a call from Shonda’s assistant, I’m like, ‘Am I in trouble?’ I always assume I’m in trouble — it still feels a little like being called to the principal’s office. But I wasn’t in trouble.”

When Rhimes and Beers told Walsh that they wanted to spin her off to her own show, she felt like it couldn’t be real.

“I just sort of like slowly left my body and watched the rest of the conversation happen from four feet above the room,” she recalled. “I really thought — I felt very grateful just to be sort of a working actor, you know, and then this happens, and you’re like, ‘Wow, my whole life has changed,’ and it’s great. It’s been very surreal.”

As the reality sunk in for Kate, and she heard what they had in mind for a story, it was easy for her to decide to do it — but not without feeling some anxiety.

“The storyline that they had pitched for me and my character was definitely, you know, exciting to me,” she said. “So I was definitely willing to take the risk. But yeah, there are a little nerves and trepidation for sure. I mean, I feel nervous only because I get nervous watching myself, you know — on television.”

Nervous or not, Walsh is thrilled with the storyline for what is tentatively titled “Private Practice,” and she’s especially happy about the new ensemble cast she’ll be working with. “I feel hugely confident in the script and we have a great cast, you know. We’ve got Tim Daly, Amy Brenneman, Merrin Dungey, Chris Lowell and Paul Adelstein. We’ve got Taye Diggs. We have a great cast.”

And what about that storyline? Is there any truth to the rumor that Addison will become pregnant on the new show?

Mum’s the word for Walsh.

“I can tell you this,” she teased. “I can tell you that I go on a little, you know, little journey — little sojourn to Southern California to go visit my friends who are doctors in private practice and yeah, it all happens from there…This is where I have to get very mysterious.”

What she will admit is that this show is going to continue the grand “Grey’s” tradition of being — you guessed it — sexy.

“Yeah, I think you’re gonna get a lot of some sweet lovin’ in the two hours of television that you’re gonna see on Thursday night,” she remarked. “Actually we do like a time lapse. We go back to the ‘60s and it’s a big crazy orgy!”

Of course she was joking about the time travel, but doesn’t rule out the possibility of a romantic relationship between her and Tim Daly’s character. “I love Tim,” she said. “I worked with him on The Fugitive and on Oz, and I just love his work. He’s a great guy, so I think our scenes will light up the screen.”

But will he have a “McDreamy” or “McSteamy”-type nickname?

“I don’t know,” said Kate. “There’s no ‘Mc’-ing available anymore!”

Walsh admitted that despite the huge success of “Grey’s” and a strong cast and script for the spin-off, there’s always the chance that the new show wouldn’t be successful. But even if that ends up being the case, she’s not concerned.

“There is a possibility of me coming back [to “Grey’s], we don’t know,” she said. “But I don’t think I’m going to have to worry. I think I’ll be okay either way. Either I’ll go back to “Grey’s” or I won’t. I might do something else for the network. I think I’ll be all right.”

Part Two of Access’ exclusive chat with Kate Walsh continues tomorrow, in which she talks about “Grey’s” behind the scenes, her modeling career, and more.

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